It cannot be like the official one. You can directly yolo predict model=yolov8s.pt source='bus.jpg' in cmd
It may be that the environment is not installed, so you need to execute pip install ultralytics
But I found that pip install reported an error again, always showing "gbk" or something like that.
I just realized that I changed the default region and language in the system's region and languange some time ago, and just changed it back to the default language to English.
After installing the requirements environment requirements, you can run yolov8 using the CLI and no error will be reported.